40004-69-1

To a stirred solution of 2-methyl-thiazole-5-carboxylic acid ethyl ester (1.3 g, 8.0 mmol) in dioxane (12 mL) at room temperature was added NaOH (2N, 12 mL). After 1 h the reaction mixture was neutralized with HCl (IN, 12 mL), then filtered and the collected solid dried in vacuo to give 2-methyl-1,3-thiazole-5-carboxylic acid (758 mg, 70percent) as an off white solid.